redrobo wrote:I think the main difference is that MSM implies that once the mirror check is done there is no more need for it. Whilst IPSGA, the I is the base stone of the system and all the other parts fit into it, implying that the information needs to be constantly updated.
That's the main difference I see too (and I'm not sure whether it's that great a difference).
When I first encountered IPSGA, I didn't have any strong feelings about the PSGA part of it, but I did like the way Information is treated in the system for two reasons: firstly the way it continues to be important throughout PSGA and you are expected (and allowed) to modify and adapt your plan part way through the hazard or manoeuvre if new information is available, and secondly because it doesn't make any mention of how to give or find information - it is your job as a driver to assess what sources of information and means of communication are available and use them as appropriate and as required.
Like others have suggested, I wonder whether the OP suffered from a tutor/observer (or examiner) who was a little more rigid than necessary.